Voltage-activated calcium channels can be distinguished based on their voltage-dependence, deactivation, and single-channel conductance. See MIM 601011. Low-voltage-activated calcium channels are referred to as 'T' type because their currents are both transient, owing to fast inactivation, and tiny, owing to small conductance. T-type channels are thought to be involved in pacemaker activity, low-threshold calcium spikes, neuronal oscillations and resonance, and rebound burst firing.[supplied by OMIM